I stopped breastfeeding 3 yrs ago but have discovered white discharge from nipples that looks like stuff from pimples. normal? no other symptoms

Nipple discharge: Any drainage from the nipples besides breast milk should be checked. It is unusual for this to continue. It may be a simple reason or something more complex. All the best.

Stuff from pimples?: Your description of this makes me think these may be normal secretions from the ducts around the nipple. Please DO have this checked out either through a PRIME consult or with your local OB. Don't forget monthly breast exams!